I have been thinking about putting a higher magnification scope on my 580-series mini-14 (I'm getting a bit long in the tooth and my eyes aren't what they used to be).

I see this excuse a lot. As you get older and eyes get worse you need more quality, not more magnification. Younger eyes can compensate better with low quaity glass. More magnification in a cheap scope doesn't help.

I was helping a friend zero his rifle back in the fall. He was using an older scope that was actually a decent scope when new 30 years ago, but newer glass is so much better. At 9X neither of us could find bullet holes at 100 yards through his scope. I had a good quality pair of 6X binoculars that easily picked up the bullet holes.